


Sans's New Body

by UYP



Category: Undertale (Video Game)
Genre: Belly Kink, Body Exploration, Chubby Kink, Male Solo, Masturbation, Other, Solo Sans, Thicc Sans, Trashfire
Language: English
Status: Completed
Published: 2020-10-07
Updated: 2020-10-07
Packaged: 2021-03-08 03:54:25
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,218
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/26879275
Author URL: https://archiveofourown.org/users/UYP/pseuds/UYP
Summary: Since it's Sans lazy day, his brother Papyrus left to do some training with Unydne, making him have the house all to himself. Immedialty, he rushes off to sleep in his bed because why not. Though, after a few hours of sleeping, Sans wakes up to an... unsual change to his body.
Relationships: Sans/Sans (Undertale)
Kudos: 12





	Sans's New Body

**Author's Note:**

> Alright so... hey guys. I'm back with another story. So, this has been in my folder for the past couple of months so I've wanted to share this with you all. Granted, this is the first story that I've ever written.
> 
> A little warning, this story does depict Sans having a humanoid body, so if don't like Sans having human body parts, then you can skip this.
> 
> Credits to @JerseyDevil for using their drawings of Sans as a reference to what he looks like.
> 
> Enjoy this cursed story!
> 
> Edit: Updated format.

It was a nice day in the Town of Snowdin. The monsters of the Underground are going about their everyday lives; hanging out at Grillby’s, reading at the town’s library, the kids playing with their friends in the snow, etc. At the end of the town, there’s a residential house that is home to the infamous skeleton brothers; Sans and Papyrus. Ever since the skeleton bros moved into Snowdin, the town became much livelier than it originally was. There’s just something about them that just brightens up in the monsters in the town. The younger brother Papyrus is a(n) enthusiastic puzzle maker and a human capturing fanatic. 

He’s been setting up all sorts of fun and challenging puzzles so that one day, he’ll finally be able to capture a human so that he can be the best of friends with and cook them his famous spaghetti. He’s also training to become the next royal guard to serve for Asgore: King of the Underground with the help of his partner, Undyne. Sans, on the other hand, is a whole nother different story. Being the older brother, Sans doesn’t do much other than sleep and slack off most of the time, though he’s fun hang out with once you get to know him.

He visits at the entrance door to the ruins to talk to Toriel, hangs out at Grillby’s to eat and drink ketchup, telling bad jokes to his friends for many hours on end. He also tends to work at his stand selling cat dogs to any passerby who’s interested. Even though he doesn’t do much in terms of work and stuff, he’s a good brother to Papyrus and fully supports him in achieving his dreams. If anything happens to their brother, he’ll make sure that person will be burning in hell for harming his brother.

But enough about that, today is Sans day off from work, or in his case, another good day to slack off. Papyrus told Sans that he would be gone for a few hours training with Undyne as well as setting up puzzles and traps in case any humans come entering the Snowdin forest. Now that he’s got the house to himself, Sans quickly rushes up to his room and locked the door behind him.

Sans’s room is much different from that of Papyrus’s room. Since his younger brother’s room reflects how he enjoys puzzles and kid stuff, Sans’s room shows how he’s much of a slob. His room has a standard drawer with a night lamp, a full-length mirror, a broken-down treadmill, an overflowing trashcan filled with crumpled up tissue paper, and a worn-out mattress with an old, stained pillow and blanket right by his bedroom window. They're also a bunch of socks that are littered all over his bedroom floor.

Despite hearing Papyrus constantly nag him to pick up his socks, he never does so. Sans took in a deep breath in and exhales out of his nostrils, ready to take a nice, long nap. He heads over to his bedroom window, closing the blinds, the room now shrouded in darkness. He climbs up to his worn mattress, covering himself with the old, unwashed blanket before sleep finally took hold of him.

Two and a Half Hours Later…

Sans was still knocked out in his bed, the sound of his sonorous snores reverberating in his bedroom. He was suddenly pulled out his sleep to the sound of his belly letting out a loud, hungry rumble, demanding for it to be fed. Hearing his belly cry out for food, Sans slowly sits up and rubs the crust out of his eye sockets before letting out a big, tired yawn. He does a big stretch, popping his limbs as he does so.

“mmmnnn?” Sans moaned sleepily, as he pushes the old blanket off of him before slowly sliding his way over to the edge of his bed.

“better see what’s in the fridge.” Some of the leftover food he got from Grillby’s would help satisfy his stomach. As Sans starts to get up from his bed, he suddenly felt a lot heavier than usual and also more… bouncier?

Slowly coming out of his drowse state, Sans turned on his bedroom lamp and headed over to his full-length mirror to see what’s wrong with him. He was shocked to find out that his body doesn’t have the same skeletal appearance anymore, instead, he now had a body that resembles more of a chubby human. 

While his face remained the same, his cheekbones seem to puff out a little bit and he also got a bit of a double chin on his neck. Now he was able to open his mouth to where he gained a set of pearly white canines and well as a neon blue tongue. Skeletons don’t have tongues, so he was baffled that he was able to have one with this new body of his, not that he’s complaining or anything. Speaking of which, his body gained a layer of soft, smooth, plush skin and muscles underneath his bones. The skin color on his new chubby form is white as snow.

His torso now had more of a bear type physique as it seems to fill out his now snug white t-shirt. His arms and hands had a gained a fair bit of muscle underneath that soft skin, but his arms still had a tiny bit of jiggly fat on them. His pectorals now had a perky pair of moobs and nipples, which outlined their soft and prominent curves underneath his tight shirt. His chubby belly produced out by a few inches, to which it rode up his t-shirt slightly, exposing a slither of his soft white underbelly while showing off the indent of his deep bellybutton through his shirt. 

Since his upper body had drastic changes to his features and appearance, his lower body, underwent a bigger change. Instead of wearing his signature basketball shorts, it’s been replaced to having a set of white briefs, which bit into his waistband tightly, giving him a muffin-top look. He’s gained a set of cock and balls which outlined the shape and size of his bulge through his tight briefs. He’s also developed pair of thick, tree-trunk thighs that rubbed against one another and ripple slightly to every move he makes.

However, his backside ballooned out into having a full-on bubble butt to which his underwear is barely containing the great chunks of ass that being squished down by his underwear. The tight briefs also gave him a bit of a wedgie, the pair sucking itself deep into his buttcrack, almost rubbing against his pucker. The tight briefs formed light folds and confluences at his inner thighs below his asscheeks, highlighting their size and heftiness. The briefs are almost like second skin with the way it’s tightly clinging to his body.

“what in the world happened to me while I was out?” Sans said confusingly as he continues to look over his new form through his reflection.

He didn’t eat anything strange that made him turn out this way, and sure he got a few desserts from Muffet’s but it never devolved into this. So, what could’ve possibly happened to him that made him turn out this way? As Sans slowly takes in his new form, he honestly thinks that this new form makes him look… good, attractive even. I mean, it’s not every day you wake up and suddenly you have a soft, teddy bear-like physique. 

Sans decides to test out his new form. He simply started by poking and prodding at his soft cheekbones. He could see his skin give in when pokes it and stretch when he tries to pull it.

“heh… feels kind of nice to have some chubby squirrel cheeks.” Sans chuckled a bit before moving his hands down to his chest.

He placed his hands down by his “underboob” and playfully bounced his chest. He giggles at the sight of seeing his chest jiggle and bounce through his shirt before giving them a gentle squeeze. Sans lets out a quiet moan of the sensation of squeezing his own chest. His new body, while smooth and soft, is also very sensitive to the touch. Sans felt himself blush a bit as his nipples slowly become erect, making them prominent through his tight t-shirt. He felt his dick twitch in his tight briefs at the sight of it, slowing growing a half-chub in his underwear. 

“whoa… didn’t think that squeezing your own chest feels that good” Sans said as he now brought his hands down to his belly and gave it a gentle rubbing.

He never had an actual belly, he sometimes used magic to makeshift a belly when he eats so it felt nice to give himself a belly rub now that he’s got one. He gave his new gut a few firm squeezes, the fat on his belly deforming around his fingers as he did so. He pulled, squished, and kneaded his belly for a few minutes, enjoying the feeling of playing with his belly. He then gave his gut a good slap, his belly rippling from the impact for a few seconds before settling.

“hehe… never thought that having a belly would be fun to play with,” Sans said as he lifted his belly up, held it for a few seconds before dropping it, his belly bounce and jiggle for a few moments before settling. His t-shirt rode up after that belly drop, showing more of his underbelly and exposing his deep bellybutton. He dipped his finger into his deep bellybutton, letting out another quiet moan before playfully bouncing his belly up and down in with his finger in his bellybutton. 

As much as he wants to play with his soft, chubby belly, there are still other places on his body that needs to be explored. Keeping one hand on his belly, Sans took his finger out of his bellybutton and slid his hand down to the front of his tights briefs while his other hand on his belly and gave his bulge and light squeeze. His dick gave another throb in his briefs as he lets out a soft moan. Sans can feel his body slowly heat up as bits of sweat started to form on his body.

After a few more squeezes his bulge, his thick cock now stood fully erect in his underwear, a wet spot forming at the tip. He rubs his dicks up and down through his brief, his wide hips going back and forth to his hand movements. The fabric of the underwear gave nice friction to his dick. That hand on his belly slowly moves up to his chest to squeeze and rub the nub of his nipple. Small sweat stains started to form on his shirt, making it cling to his body.

Sans softly pants as he continues to masturbate through his briefs while rubbing and squeezing his chest. His dick throbs a few times, the wet spot on tip of his briefs slowly growing bigger. “holy shit… how’d I didn’t know how good this felt?” Sans said as he starts to get more comfortable by taking off his shirt and briefs, finally freeing his cock from its cotton prison as well as revealing his body in all of its glory. His cock stood high and tall at a reasonable 7 inches with a pair of sizable balls underneath. Continuing where he left off, Sans wrapped his hand around his dick once again, rubbing it up and down, slightly bucking his hips a bit to the motion. Heavy pants as well as lewd, wet slick sounds resonate within the bedroom. Sans can feel himself getting closer as he slowly picks up the pace. 

Finally, Sans lets out a loud moan as finally reached his climax, his body rippling in pleasure as several spurts of monster spunk shoot out of his dick splashing against his mirror and bedroom floor. With his orgasm subsided, Sans collapsed onto the floor, basking in the afterglow as his body felt hot and sweaty. After a few minutes, Sans finally gets up and puts backs on his now sweaty shirt and briefs before taking another look at his reflection.

“God damn, I don’t think I want don’t to go back to my old body after that experience,” Sans said, showing off and admiring his body by doing a few little poses.

Suddenly his belly lets out another hungry rumble, his belly rippling slightly to the sound of it. Sans chuckles at his belly by giving a soft, firm pat.

“guess all that self-worship is making me hungry.”

After giving himself one last look over, he heads over his bedroom door. He can feel himself blush again at the feeling of his thighs rubbing against each other and his asscheeks clapping against one another. He doesn’t know how’ll he’ll explain this new body to Papyrus when he comes back. So, he hopes that he’ll come to terms and accept this new body of his when he comes home. Sans opened his door and made his way door stairs to the kitchen, his body bouncing and rippling as he does do.

Who knows, maybe he’ll get to share this experience with someone someday. 

The End


End file.
